Current mode control is a known solution to control a DC-to-DC converter. A DC-to-DC converter generally provides a constant output voltage or small output voltage range (e.g. a few hundred millivolt). However, the current mode control may suffer from instability when a duty cycle of its output control signal is higher or lower than 50%, i.e., instabilities may be caused if the output control signal is active for more or less than half of the signal period. In order to avoid instability, slope compensation is used.
Although its principles of operation may correspond to those of a DC-to-DC converter, conventional approaches for slope compensation may not be used for current mode control of an amplifier's output stage since the output stage of an amplifier provides a full-swing output voltage instead of a constant voltage or a small output voltage range like a DC-to-DC converter. For example, an amplifier's output stage may provide a signal having a form substantially equal to a sine wave. The amplifier's output signal may have a dynamic range up to several Volts, swinging from one end of the output range to the other within short time instants. With the full-swing output voltage having a higher dynamic range compared to an output range of a DC-to-DC converter, conventional approaches for slope compensation may generate disturbances and distortions at the output of the amplifier's output stage or do simply not work. Hence, there may be a desire for improved current mode control for an amplifier.